Kind of looks like pascals triangle, i can't find the pattern the professor said

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SUMMARY

The discussion centers on a method for generating a sequence resembling Pascal's Triangle to determine the number of equivalence relations on a set with 5 elements, which totals 52. The user initially struggles to understand the professor's technique for deriving the next row of the triangle. After collaboration with a peer, they conclude that the next row can be calculated by multiplying each number by its position, adding it to the leftmost number. The final derived row is 1, 31, 90, 65, 15, 1.

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Hello everyone. I have the following problem that can be solved using a traingle that looks similar to pascals triangle, but i must have have misunder stood the professors method of finding the next row. I have a final tomarrow and learning this technique would help but he told us on the last day of class so i didn't have time to ask him again what he did.The problem wants me to find out how many transitive, symetirc, and reflextive binary relations on S that has 5 elements. Well if somthing is transitive, symetric, and relfextive its just an equivlance relation, and a equivlance relation is just another way of saying, how many partitions exists in a set that has 5 elements? Well the answer is: 52.

Here is how the professor found it:
1
1 1
1 3 1
1 7 6 1
1 15 25 10 1

that's the 5th row down so 1 + 15 + 25 + 10 + 1 = 52, from what it looks like he is multiplying the first 1 in the 2nd row, by 2, then adding 1 = 3. then taking 3 * 2 + 1 = 7; but then i don't see how he is getting 6. I also see that he is taking 7*2 + 1 = 15, but I'm lost on how he found 25 and 10, any ideas? thanks.
 
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With the help of a friend i figured it out:
you just take the number * its positon add it to the left most number to get ur next number.
so the next row would be:
1 15*2 + 1 25*3+15 10*4 + 25 + 1*5 + 10
1 31 90 65 15 1
 

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